Selvage uncurler and method of uncurling selvages of webs



June 13; 1967 G. P. KNAPP ETAL SELVAGE UNCURLER AND METHOD OF UNCURLING SELVAGES OF WEBS 2 Sheets-Sheet 1 Filed Dec. l7. 1964 FIG. 2

' INVENTORS GEORGE E KNAPP N A E D E Du E U A W Y B ATTORNEYS June 13, 1967 G. P. KNAPP ETAL SELVAGE UNCURLER AND METHOD OF UNCURLING SELVAGES OF WEBS 2 Sheets-Sheet 2 Filed Dec. l7, 1964 FIG. 4

m w O m WW 1 EMM m W 1 PE ER GE m E w G W Y B O Q 4 ATTORNEYS 3,324,525 SELVAGE UNCUR-LER AND METHOD OF UNCURLHNG SELVAGES F WEliS George ll. Knapp, Waban, and Walter E. Dean, Taunton,

Mass, assignors to Mount Hope Machinery Qompany,

Taunton, Mass, a corporation of Massachusetts Filed Dec. 17, 1964, Ser. No. 420,856 4 Claims. (Cl. 26-54) This application is a combination-in-part of our United States patent application Ser. No. 190,615, filed Apr. 27, 1962, entitled, Selvage Uncurler for Webs, and now abandoned.

This invention pertains to an improved selvage uncurler for traveling webs, and to an improved method for uncurling selvages. In the handling of traveling webs, especially of stretchable materials such as textiles, the edges or selvages of the web frequently are found to curl laterally toward the central portions. If the selvages are not subsequently uncurled, an appreciable fraction of the width of the goods is effectively lost; subsequent operations performed on the web, such as guiding, sizing, or printing cannot be carried out properly; and the goods cannot be wound into a uniform roll because of the excess thickness at the edges due to their being doubled over. Devices have been previously developed for uncurling selva-ges, but they have generally been found ineffective in handling fragile knit goods or other web materials which are highly stretchable and which must, therefore, be handled at low levels of tension.

It is the primary object of our invention to provide a selvage uncurler, and a method of uncurling selvages, which is effective in handling web materials of all kinds, including those of a highly stretchable or fragile variety which may be subjected only to very limited tension. It is a further object of our invention to provide an improved selvage uncurler which features a positive uncurling action and is effective even on curls of several convolutions. It is still another object of our invention to provide an improved selvage uncurler which is readily adjustable to remove varying degrees of curl from diverse types of webs without unduly stretching or otherwise injuring the web.

Briefly stated, according to a preferred embodiment thereof in selvage uncurling apparatus, we may carry out our invention by providing a pair of wheels each of which is formed with a circular row of teeth terminating substantially in a common plane normal to a rotational axle of the wheel. The axles of the wheels are mounted by means of .angularly adjustable clamps to position the planes of their teeth in confronting relation for receiving the selvage of a web for translation therebetween, being adjustable to cant the axes of rotation of the wheels and the planes of the tooth tips at an angle with respect to the plane of the web.

According to the method of our invention, selvage uncurling wheels are adjusted in angle and spacing in such a manner that a limited arcuate sector of their rows of teeth interengage with one another. The axles are then inclined longitudinally of the web in the direction of its travel, and laterally of the web toward its center, so that the sector of engaged teeth extends arcuately at least from a point at which the longitudinal dimension of the web is tangent to the tooth circles, to the point at which the selvage of the web departs from the teeth. These steps cause the engaged teeth in the entering portion of the arc to act primarily to rotate the wheels, and those teeth in the exit portion of the arc to act primarily to pull the selvages laterally to uncurl them.

The grip in the first part of the arc produces a circumferential torgue which rotates the wheels about their axles at a maximum rate, without need for other motive means.

3,324,525 Patented June 13, 1967 The induced rotation produces lateral reaction components outwardly toward the selva-ges, and these components reach a maximum in the last part of the arc.

This method is effective to remove curl, and does not damage the web when the wheels are properly adjusted as to the angle of cant of the axles transversely and longitudinally of the plane of the web, and also as to the extent of inter-engagement of the teeth with the web laterally and normally thereof. The degree of flexibility of the protrusions or teeth may also be selected to suit the ma terial. A wide variety of flexible web materials may be satisfactorily uncurled without producing deleterious longitudinal or lateral distortion.

While the specification concludes with claims particularly pointing out the subject matter which we regard as our invention, it is believed that a clearer understanding may be gained from the following detailed description of preferred embodiments thereof, referring to the ac companying drawings, in which:

FIG. 1 is a plan view showing a pair of selvage uncurlers according to the invention, in cooperating relation with a traveling web arranged to be uncurler thereby;

FIG. 2 is a sectional view in elevation of one of the selvage uncurlers, taken along line 22 in FIG. 1, looking in the direction of the arrows;

FIG. 3 is a diagram of reaction forces exerted upon the web by interenga-ged teeth located at various angles about the axes of rotation of wheels of the uncurler;

FIG. 4 is an enlarged plan view of a selvage uncurler in an unadjusted relationship of the wheels; and

FIG. 5 is a sectional View in elevation taken along line 5-5 in FIG. 4.

Referring to the drawings, our improved selvage uncurler generally comprises a pair of wheels generally designated 10, each comprising a disc 12 having circumferentia lly spaced thereabout a plurality of teeth or protrusions M, which are preferably formed of a flexible material such as rubber, and terminate in angular tips 16 extending in a circular row in a common plane. The teeth shown are of a preferred arcuate form, extending radially and axially from the discs 12; but various forms of teeth or protrusions may be alternatively used. For example, the wheel might be formed as a rubber disc having a convoluted surface. Each of the teeth is affixed to its disc by a machine screw 18 threadedly engaged in the disc, or by other suitable fastening means, which are removable for replacement of individual teeth. Alternatively, the teeth may be molded in a common disc (not shown) of rubber, plastic, or the like, attached to the disc 12 by removable fasteners. Each of the discs 12 is formed with a central boss 20, in which is press-fitted an axle 22. A bearing assembly 24 of any conventional type is secured on each axle for rotatably supporting the associated wheel.

The wheels of each uncurler are mounted with the rows of teeth 14 in opposed relationship, and for universal adjustability of their axes of rotation, by means of a U-shaped bracket 26 having generally spherical split clamps 28 at the ends of the legs thereof. The clamps 28 receive spherical bearing blocks 30 therein, and adjustable clamping engagement is obtained by means of screws 32 threaded through mating flanges 34. Each bearing block 30 is radially split at 35 for clamping an annular sleeve 36 therein. The sleeves 36 are radially flexible, for clamping bearing assemblies 24 therein in axially-adjusted positions. This axial adjustability is limited by abutment of the bearings against circumferential shoulders 38. It will be apparent that by loosening the screws 32 to relieve the clamping engagement of the bearing blocks 30 therein, the axes of rotation of each of the wheels 10 may be canted at any desired angle laterally and longitudinally of the plane of a web passing transversely between the wheels. Further, the extent of tooth engagement may be adjusted by moving the axles longitudinally in the sleeves 36. For mounting the selvage uncurler assembly, a bracket 40 is secured to one leg of the U-shaped bracket 26 by means of threaded fasteners 42. The bracket 40 should be supported for adjustment movement transversely of the web, to accommodate various widths of web, and also to secure effective action on curls of varying widths.

Referring now to FIG. 1, a pair of the improved selvage uncurlers, generally indicated at 44, are arranged in operative relation to a web 46 traveling in the direction shown by the arrow in the plane of the paper, which is substantially normal to the axes of rotation of the wheels of each uncurler in an unadjusted coaxial relationship thereof. The web is shown with its selvages 48 entering the uncurlers somewhat curled as at 50. It should be noted that the brackets 26 are positioned to support the wheels so that only a minor segment of the tooth circle of each wheel overlies the web. In the unadjusted relationship of the wheels 10 shown in FIG. 5, they produce substantially no effect upon the web, there being sufficient clearance between the confronting teeth of each pair of wheels for free passage.

To effect uncurling of the selvage according to our improved method, the axles of the wheels are canted at an angle in the brackets 26 as shown in FIG. 2, and are inclined longitudinally of the web in the direction of its travel, and laterally thereof inwardly, in such a manner that of the arcuate segment of teeth shown overlying the web in FIG. 1 and indicated by the tooth circle 51 in FIG. 3, only those in arcs ,8 and 'y actually engage the web, while the remaining arcuate segment a passes freely over the selvage of the goods. The opposing teeth interengage at point X, and disengage slightly beyond the offgoing selvage indicated at Z, reaching an intermediate point of maximum engagement Y which is angularly spaced intermediate the directions of the lateral dimension and longitudinal travel of the web. The web consequently passes in a zig-zag path between the interengaged teeth, as indicated in dotted lines in FIG. 2.

The effect of the interengagement of the teeth with the web will be more clearly understood from an inspection of FIG. 3, in which the reactions produced upon elements of the web with the engaging teeth at various angular positions is indicated. The locus of the teeth comprises the circle 51, and the reaction forces of the teeth on elements of the web are shown at Px, Py, and Pz for elements passing the corresponding points on the tooth circle. The web, engaging the teeth only in the are {3-7, produces rotation of the wheels in the direction shown by the circular arrow. The reactions Px and P2 are of relatively minor values, inasmuch as the teeth remain interengaged only slightly at point Z, and are just entering engagement at point X. The reaction at point Y, at which the teeth attain maximum engagement, is relatively large, and includes a circumferential component C and a radial component R. It will be apparent that the reactions induced at various points along the arcs B and 'y will be comprised of components whose relative values are determined by their particular angular position.

The circumferential component C produces rotation of the wheel, and the radial component R produces tension in the web which is principally in a lateral direction, and therefore tends to uncurl the web. In the are p, the radial component is of relatively minor importance, and this are may be considered as a torque-applying sector, which primarily serves to induce rotation of the wheels. For this reason, it is not necessary to drive the wheels with a motor. In the arcuate sector 'y, a relatively large radial component appears because of the rotation produced in the are a; this component in turn includes a major component of lateral pull on the web, and this are therefore may be characterized as an uncurling sector.

It will be evident from a consideration of the geometry of the intersecting tooth circles that the teeth disengage at a point forming an angle with point Y which is equal to angle 5; however, it is found preferable in actual practice that the point of disengagement fall somewhat beyond the selvage 48, and, therefore, angle '7 is somewhat smaller than angle 6. It should be noted that the point X of initial tooth engagement must be spaced at a substantial angle a from the entering selvage 48, since any lateral component against the entering web will be directed inwardly rather than outwardly, and would merely tend to increase the curling of the selvages.

The selvage uncurler should be adjusted in actual practice to produce the optimum uncurling effect with minimum distortion for a given type and weight of fabric. Not only the angle of inclination of the axes of the cooperating wheels may be adjusted laterally and longitudinally of the web, but the spacing between the wheels in a direction normal to the plane of the web may also be adjusted to control the magnitude of the reaction forces produced in the web by the wheels. The material of the teeth may also be selected to secure a proper degree of flexibility as may be found suitable for web materials of varying weight and delicacy. The teeth need not be individually formed as shown, but might comprise irregular or scalloped surfaces formed in a single flexible body; further, the specific form selected for the tooth tips is not believed to be critical.

Various additional changes and modifications will readily occur to those skilled in the art, without departing from the true spirit and scope of the invention.

What we claim and desire to secure by Letters Patent of the United States is:

1. The method of uncurling the selvage of a longitudinally-traveling web by means of a pair of wheels each having a circular row of elongated arcuate teeth protruding outwardly and terminating in a circular plane, which comprises the steps of: supporting the wheels in confronting relation, for passage of an edge of a longitudinallytraveling web between them, and for free rotation by the movement of the web; and inclining the rotational axes of said wheels in the direction of travel of the web and laterally of the web toward its center, while interengaging the rows of teeth with an overlap normal to the web of suflicient magnitude in relation to the diameter and inclination of the wheels to grip the web edge about an are extending at least from a point at which the teeth travel with a principal component of direction parallel to the length of the web, to a point at which the web edge departs from the tooth circles and the teeth travel with a principal component of direction parallel to the lateral dimension of the web, whereby teeth in the entering portion of said are act primarily to rotate said wheels with a maximum angular velocity corresponding to the velocity of web travel, and teeth in the exit portion of said are act primarily to pull laterally on the web.

2. The method recited in claim 1, in which the step of interengaging the rows of teeth is carried out with the arc of interengagement extending at least from a point at which the longitudinal dimension of the web is tangent to the tooth circles, to the point at which the web edge departs from the tooth circles.

3. A selvage uncurler comprising, in combination: a pair of confronting wheels, each having a circular row of elongated arcuate teeth protruding outwardly and terminating in a circular plane, for passage of an edge of a longitudinally-traveling web between them; and bearing means supporting said wheels for rotation on canted axes which are inclined in the direction of travel of the web, and are also inclined laterally of the web toward its center, said wheels being free for rotation by the movement of the web therebetween; said wheels being supported by said bearing means with the planes of termination of the rows of teeth intersecting and an arcuate sector of each row of teeth interengaged to grip a curled web edge; said teeth being formed of a length, in relation to the diameter and inclination of said wheels, to interengage over an arcuate sector extending at least from a point at which said teeth travel with a principal component of direction parallel to the length of the web and act primarily to rotate said wheels with maximum torque, to a point at which the web edge departs from the tooth circles and said teeth travel with a principal component of direction parallel to the lateral dimension of the web and act primarily to pull laterally on the web to uncurl its edges.

4. A selvage uncurler as recited in claim 3, in which said interengaged arcuate sector of teeth extends at least from a point at which the longitudinal dimension of the web is tangent to the tooth circles, to the point at which the web edge departs from the tooth circles.

References Cited UNITED STATES PATENTS ROBERT R. MACKEY, Primary Examiner. 

1. THE METHOD OF UNCURLING THE SELVAGE OF A LONGITUDINALLY-TRAVELING WEB BY MEANS OF A PAIR OF WHEELS EACH HAVING A CIRCULAR ROW OF ELONGATED ARCUATE TEETH PROTRUDING OUTWARDLY AND TERMINATING IN A CIRCULAR PLANE, WHICH COMPRISES THE STEPS OF: SUPPORTING THE WHEELS IN CONFRONTING RELATION, FOR PASSAGE OF AN EDGE OF A LONGITUDINALLYTRAVELING WEB BETWEEN THEM, AND FOR THE FREE ROTATION BY THE MOVEMENT OF THE WEB; AND INCLINING THE ROTATIONAL AXES OF SAID WHEELS IN THE DIRECTION OF TRAVEL OF THE WEB AND LATERALLY OF THE WEB TOWARD ITS CENTER, WHILE INTERENGAGING THE ROWS OF TEETH WITH AN OVERLAP NORMAL TO THE WEB OF SUFFICIENT MAGNITUDE IN RELATION TO THE DIAMETER AND INCLINATION OF THE WHEELS TO GRIP THE WEB EDGE ABOUT AN ARC EXTENDING AT LEAST FROM A POINT AT WHICH THE TEETH TRAVEL WITH A PRINCIPAL COMPONENT OF DIRECTION PARALLEL TO THE LENGTH OF THE WEB, TO A POINT AT WHICH THE WEB EDGE DEPARTS FROM THE TOOTH CIRCLES AND THE TEETH TRAVEL WITH A PRINCIPAL COMPONENT OF DIRECTION PARALLEL TO THE LATERAL DIMENSION OF THE WEB, WHEREBY TEETH IN THE ENTERING PORTION OF SAID ARC ACT PRIMARILY TO ROTATE SAID WHEELS WITH A MAXIMUM ANGULAR VELOCITY CORRESPONDING TO THE VELOCITY OF WEB TRAVEL, AND TEETH IN THE EXIT PORTION OF SAID ARC ACT PRIMARILY TO PULL LATERALLY ON THE WEB.
 3. A SELVAGE UNCURLER COMPRISING, IN COMBINATION: A PAIR OF CONFRONTING WHEELS, EACH HAVING A CIRCULAR ROW OF ELONGATED ARCUATE TEETH PROTRUDING OUTWARDLY AND TERMINATING IN A CIRCULAR PLANE, FOR PASSAGE OF AN EDGE OF A LONGITUDINALLY-TRAVELING WEB BETWEEN THEM; AND BEARING MEANS SUPPORTING SAID WHEELS FOR ROTATION ON CANTED AXES WHICH ARE INCLINED IN THE DIRECTION OF TRAVEL OF THE WEB, AND ARE ALSO INCLINED LATERALLY OF THE WEB TOWARD ITS CENTER, SAID WHEELS BEING FREE FOR ROTATION BY THE MOVEMENT OF THE WEB THEREBETWEEN; SAID WHEELS BEING SUPPORTED BY SAID BEARING MEANS WITH THE PLANES OF TERMINATION OF THE ROWS OF TEETH INTERSECTING AND AN ARCUATE SECTOR OF EACH ROW OF TEETH INTERENGAGED TO GRIP A CURLED WEB EDGE; SAID TEETH BEING FORMED OF A LENGTH, IN RELATION TO THE DIAMETER AND INCLINATION OF SAID WHEELS, TO INTERENGAGE OVER AN ARCUATE SECTOR EXTENDING AT LEAST FROM A POINT AT WHICH SAID TEETH TRAVEL WITH A PRINCIPAL COMPONENT OF DIRECTION PARALLEL TO THE LENGTH OF THE WEB AND ACT PRIMARILY TO ROTATE SAID WHEELS WITH MAXIMUM TORQUE, TO A POINT AT WHICH THE WEB EDGE DEPARTS FROM THE TOOTH CIRCLES AND SAID TEETH TRAVEL WITH A PRINCIPAL COMPONENT OF DIRECTION PARALLEL TO THE LATERAL DIMENSION OF THE WEB AND ACT PRIMARILY TO PULL LATERALLY ON THE WEB TO UNCURL ITS EDGES. 